Automatic safety nozzle



Oct. 24, 1961 R. M. KLAUS AUTOMATIC SAFETY NOZZLE Filed March 11, 1960INVENTOR. 190 mm M /(LA(/s,

dub) Y W AT TO RNEYS.

United States Paten v 3,005,476 AUTOMATIC SAFETY NOZZLE Richard M.Klaus, Cincinnati, Ohio, assignor, by mesne The invention relates tonozzles such as are used with preset computer type gasoline dispensingpumps, the nozzles having automatic valve-closure means, responsive to asensing means, for interrupting the flow of fuel through the noule whenthe tank into which the fuel is being introduced reaches a predeterminedfilling level.

A typical form of such nozzle is shown and described in the Duerr Patent2,582,195. As is well known in such nozzles, there is a main valve whichis operated by a lever having a latch means adapted to hold the lever inthe open position. The lever, however, is pivoted to a supplementaryplunger mechanism which, being actuated by a diaphragm made responsiveto the sensing means, serves to move the lever to a valve-closingposition, irrespective of the latch means, when the desired height offill has been achieved in the tank. While the valves in such nozzles maybe manually closed by the operator, they do not close automaticallyexcept in response to the sensing means. The operation of the diaphragmin response to the sensing means is dependent upon the continued flow ofthe fuel through the nozzle. It follows that, if for some reason thepressure of fuel ahead of the nozzle decreases or is interrupted, thenozzle valve will remain open until manually closed.

This is a disadvantage in the operation of automatic nozzles for severalreasons. If the pressure ahead of the nozzle is eliminated, it ispossible under some circumstances that reverse flow of the fuel willtake place through the nozzle. A cessation of flow of the fuel throughthe nozzle into the tank by reason of a failure of pressure ahead of thenozzle may be mistaken by the operator for the automatic closure of thenozzle due to the filling of the tank. Thus the operator may withdrawthe nozzle and hang it on the pump housing before the customers tank hasbeen filled, and with the nozzle valve still in the open condition. Arestoration of the pressure ahead of the nozzle may then cause a flow offuel through the nozzle with consequent loss of fuel.

It is a primary object of the invention to provide an automatic nozzlestructure wherein the main nozzle valve will close if a substantialdiminution or failure of fuel pressure occurs ahead of the nozzle.

This object and others which will be apparent to one skilled in the artupon reading these specifications, or which will be set forthhereinafter, is attained by that construction and arrangement of partsof which an exemplary embodiment will now be described. The exemplaryembodiment has to do with an automatic dispensing nozzle of the typeshown in the Duer-r patent to which reference has been made; but it willbe understood that the principles of the invention are applicable toother types of automatic shut-off nozzles.

Reference is made to the drawing 'which illustrates in longitudinalsection the exemplary nozzle embodiment.

The automatic dispensing nozzle has a hollow body 1 with a fuel entranceportion 2 and a spout 3. It is provided with a main valve 4 having anoperating stem 5, and a relatively strong spring 6 biasing the valve tothe closed position. An operating engage the valve stem and open thevalve when the lever is drawn upwardly. The lever is pivoted'as at 8 toa yoke 9 on the end of a plunger '10. The upper position of the lever isshown in dotted lines in the drawing; and this handle 7 is positioned totails of this apparatus reference may be had to the Patented 24, 1961position is maintained by a latch means 11, all as is well known in theart. The plunger 10 is part of a. sensing means which, when the tank isfull, permits the plunger 10 to descend. Thus the pivot point 8 of theoperating lever is moved a sufficient distance to permit closure of themain valve 4 despite the fact that the outer end of the lever is stillengaged. by the latch 11. For the de- Duerr patent.

The present invention makes use of the conventional vacuum diaphragm 12which extends across a chamber 13. The chamber, however, is providedwith a second diaphragm 14 held in spaced relationship to the diaphragm12 by a ring member v15. The chamber 13 is provided with a cap or topclosure 16 which may be held in place by screws or in any other suitablefashion.

The effective area of the diaphragm 14 is made to be substantially lessthan the effective area of the diaphragm 12 through the use of washershaped elements 17 and 18 located on either side of the diaphragm 14.

In the exemplary embodiment, the stem 5 of the main valve 4 is providedwith a conical element 19 which, when the valve is open, produces aventuri effect in the flowing stream of fuel, so that avacuum is drawnin an annular space 20 surrounding the valve. This space is connected bya passageway 21 through the wall of the chamber 13, and by a passageway22 in the ring to the space between the di-aphragms 12 and 14. It willbe understood that the diaphragm 12 has a perforation at the point ofconnection between the passageways 21 and 22. The vacuum drawn in thespace between the diaphragms 12 and 14 is normally relieved by aconnection to the outer air through a sensing means. This connectioncomprises a passageway 23 in he ring 15 and another passageway 24 in thewall of the chamber 13. These passageways are in communication with eachother. The passageway 24 is connected to a suitable sensing means. Inthe particular embodiment this sensing means is a tube 25 extendinginteriorly of the spout member 3 and opening to the atmosphereexterior-1y of the spout at 26. Other types of sensing means may,however, be used, such as a fitting built into the tank which is beingfilled, the fitting being connected to the passageway 24 by a flexibleconduit. 1

The space between the cap or cover member 16 and the diaphragm 14 isconnected back by means of a tube 27 to the entrance portion 2 ofthenozzle structure at a point ahead of the main valve 4.

The plunger 10 is urged upwardly by the usual spring 28. The plunger mayhave the usual locking means com prising a plurality of balls, one ofwhich is shown at 29. These balls engage in perforations in the plunger10, and in their outermost positions will engage a shoulder 30 in thewall of the chamber 13. The plunger 10 is hollow, as shown, and a pinelement slides within it. This pin element has a portion 31 of adiameter sufficient to keep the balls 29 in their outermost positions,and a smaller portion 32 which will permit the balls to ride inwardly,unlocking the plunger 10 and permitting its descent to change the pivotpoint of the operating lever as hereinabove explained. The pin also hasan abutment means 33; and a spring 34 is engaged between this abutmentmeans and the bottom of the hollow in the plunger 10.

The pin is fastened to the diaphragm :12 by nuts 35 and 36, there beinga washer 37 positioned against the upper side of the diaphragm. The pinis also fastened to the diaphragm 14 bv means of a screw 38 and a washer39.

' The operation of the apparatus is as follows: so long as fuel pressureis maintained in the entrance portion 2 of the dispensing nozzle, anequivalent fuel pressure will be maintained in the space between the capor cover 16 and the upper diaphragm 14. This urges the central portionof the diaphragm downwardly and takes the place of the usual diaphragmspring. It will serve to maintain the pin element in the position shownin the drawing, wherein the pin enlargement 32 keeps the balls 29 intheir outward or locking positions.

The structure operates in the ordinary way as an automatic shut-offnozzle because, should an obstruction occur at the point26 of thesensing means, as when the fuel reaches that point in the operation offilling the tank, the increased vacuum in the space between thediaphragm 12 and the diaphragm- 14 will cause the diaphragm 12 to moveupwardly, shifting the pin to a position at which the balls 29 can moveto unlock the plunger 10. It will there is atmospheric pressure on theunderside of the diaphragm 12, and the reason why the move upwardly uponan increase in the vacuum in the space between the two diaphragms, isbecause the effective area of the diaphragm 12 is made to be so muchlarger than the effective area of the diaphragm 14 that the tendency ofthe diaphragm 12 to move upwardly under the influence of the increasedvacuum will be greater than the tendency of the tree portion of thediaphragm 14 to ove downwardly under the pressure of the fuel.

If, however, the pressure of the fuel in the space be tween the cap 16and the diaphragm 14 should fail or significantly diminish, the force ofthe spring 34 will raise the pin to a position in which the plunger isunlocked.

In either event, once the plunger 10 is unlocked, it will movedownwardly because the force of the spring 6 on the main valve isgreater than the force of the spring 28 on the plunger. It will thus beapparent that the main valve of the dispensing nozzle will close eitherunder the influence of the sensing means, or upon failure or significantdiminution of the fuel pressure ahead of the nozzle, thus accomplishingthe main object of the invention.

The main valve will remain shut 013? until the operator starts the pumpand opens the valve again. This prevents the draining of the fluidbehind the main valve. The arrangement of this invention works betterthan a check valve at the entrance side of the nozzle since with a checkvalve alone the fluid between the check valve the main valve could bedrained by opening the main valve. With the mechanism described hereinthe main valve cannot be opened unless pressure is in the line to thenozzle entrance portion 2.

Modifications ofthe invention may be made without departing from thespirit of it. The invention having been described in an exemplaryembodiment, what is claimed as new and desired to be secured by LettersPatent is:

1. An automatic dispensing nozzle comprising a hollow body having aninlet means, a valve, manual operating means for opening said valve,means for latching said operating means in the valve-open position, andrelease means acting on said operating means to permit closure of thesaid valve, a chamber on said body, a pair of diaphragms in spacedconcentric relationship in said chamber, a common connection betweenboth of said diaphragms and said release means, means for producing avacuum between said diaphragms whereby, due to the action of a sensingmeans, one of said diaphragms having a side open to atmospheric pressuremay be moved to actuate said release means against the resistance of thesecond diaphragm, and means in connection with the inlet means of saidnozzle for imposing upon the second of said diaphragms the pressure offluid ahead of said nozzle, whereby failure or substantial diminution ofsaid pressure will actuate. said second diaphragm to operate saidrelease means.

2. The structure claimed in claim 1. wherein the effective, area of thefirst mentioned: diaphragm is. larger than the. efiiective area of the.second mentioned diaphragm. so

that a vacuum acting on said first mentioned diaphragm can overcome theeffect of fuel pressure against said second mentioned diaphragm.

3. In an automatic dispensing nozzle, a hollow body comprising fluidentrance means, a spring actuated main valve with a stem, a manualoperating lever positioned to actuate said valve stem whereby to opensaid valve, latch means for engaging one end of said lever to hold it invalve-opening position, the other end of said lever being pivoted to aslidable plunger, locking means to prevent sliding movement of saidplunger, said plunger being adapted, when said locking means isreleased, to move the pivot point of said lever to a position at whichsaid main valve will close, a. chamber on said body, a first diaphragmin said chamber having a side open to atmospheric pressure, a seconddiaphragm in said chamber concentric with and spaced from the firstdiaphragm, a closure for the end of said chamber, means in connectionwith the flow of fluid through said nozzle for creating a vacuum in aspace, means for connecting said-space with the space between the twodiaphragms, a sensing means in connection with the space between saidtwo diaphragrns and acting normally to relieve the vacuum therebetween,means for applying the pressure of fluid in the entrance means of saidnozzle against the outer side of said second diaphragm, and a mechanicalconnection between said diaphragms and to the locking means for saidplunger whereby movement of either diaphragm in a direction away fromsaid plunger will release said locking means allowing movement of saidplunger and consequent closure of said main valve.

4. The structure claimed in claim 3 wherein the eifective area of thefirst diaphragm is larger than the eifective area of said seconddiaphragm whereby vacuum in the space between said diaphragms willovercome the effect of fluid pressure against said second diaphragm.

5 The structure claimed in claim 4 wherein said plunger has a springtending to return it to locked position and wherein said main valve hasa stronger spring tending to urge it to the closed position.

6. The structure claimed in claim 5 wherein said locking means comprisesa pin slidable internally of said plunger, said pin having portions ofdiflerent effective diameters, and a series of balls operating throughthe wall of said plunger and engaging a shoulder on said body, anenlarged portion of said pin normally holding said balls in the lockingposition, said pin being movable in a direction longitudinally of saidplunger to a position in which a reduced portion of said pin allows saidballs to retract and release said plunger, and a spring acting on saidpin to urge it to the releasing position, the effect of normal fluidpressure against said second diaphragm being suflicient to overcome theforce of said spring.

7. The structure claimed in claim 6 wherein the means for creating avacuum includes means at said main valve acting in connection with theflow of fluid therethrough to produce a venturi effect.

8. In an automatic dispensing nozzle, a valved hollow body through whicha fluid is to be dispensed, a chamber in connection with said body, afirst diaphragm spanning the walls of said chamber, a ring surmountingsaid first diaphragm, a second diaphragm scanning said ring, and aclosure cap for said chamber, said elements respectively defining aspace within said chamber below said first diaphragm which space is atatmospheric pressure, a second space Within said chamber between saiddiaphragms which space may be subjected to a vacuum for automaticshut-ofi purposes, and a space above said second diaphragm, which spacehas a fluid connection to the entrance side of said nozzle, means foropening the valve, means for holding the valve in open position, releasemeans for said last mentioned means, and. a connection between saidrelease means and both of said 6 diaphragms whereby movement of eitherdiaphragm will space between said diaphragms will overcome the eifect beeffective in operating said release means. of fluid pressure againstsaid second diaphragm.

9. The structure claimed in claim 8 including rigid washer-shapedelements on either side of said second References Cited in the file ofthis Patent diaphragm whereby to reduce the effective area thereof 5UNITED STATES PATENTS to a value substantially below the effective areaof said 2,011,393 Bradley Aug- 13 1935 first diaphragm whereby theeffect of vacuum in the Notiee 0f Adverse Deeisien in interference InInterference N 0. 92,586 involving Patent N 0. 3,005,476, R. M. Klaus,Automatic safety nozzle, final judgment adverse to the patentee Wasrendered May 25, 1962, as to claims 3 and 8.

[Offi'cz'al Gazette June 26, 1962.]

